NextDNS CLI - failover problem?!

Today my network suddenly stopped working several times and the reason was DNS-issues according to the logs on my ASUS AX86U (with Merlin 386.1_2). My two primary nodes it selects are estnoc-cph and anexia-cph according to the logs.

The problem seems to be that NextDNS CLI doesn't sense when DNS-queries fails and  immediately switches over to another working PoP. Queries are queued on the router and dnsmasq seems to overflow (see logs below).

Today it seemed like the problem was with anexia-cph, because it worked when estnoc-cph was selected during a restart. NextDNS CLI switched over to the non-working PoP since it sometimes are a few milliseconds faster even though DNS-queries fails and my network goes down again.

A few lines from my logs:

Feb 16 13:54:45 nextdns[1963]: Endpoint provider failed: &{dns.nextdns.io. https://dns.nextdns.io#45.90.28.0,2a07:a8c0::,45.90.30.0,2a07:a8c1::}: exchange: roundtrip: read tcp xx.xx.xx.xx:39762->45.90.28.0:443: read: connection timed out
Feb 16 13:54:52 dnsmasq[2421]: Maximum number of concurrent DNS queries reached (max: 150)
Feb 16 13:55:06 nextdns[1963]: Received signal: broken pipe (ignored)